Organizing丨Noah

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As we all know, the world's IPv4 addresses have long been exhausted.

On November 25, 2019, the European Network Information Coordination Center officially announced that 4.3 billion IPv4 addresses around the world have been allocated. Since then, IPv6 has been highly anticipated as the latest version of the Internet protocol. However, in fact, except for a few companies, the overall advancement of IPv6 has been quite slow.

More than four years after IPv4 addresses were used up, cloud service giant AWS made a decision: starting from February 1, 2024, public IPv4 addresses will be charged.

This news immediately caused a lot of discussion. Among them, Paul Copplestone, co-founder of the open source BaaS platform Supabase, published a public article "Cheer up, IPv6 is coming" to discuss the impact of this incident.

He bluntly mentioned that for companies like Supabase that build their IT infrastructure layer based on AWS, the impact cannot be underestimated. "We provide a full EC2 instance for every Postgres database, so this will add millions of dollars to our AWS bill."

1. Charges suddenly started: $0.005 per IP per hour

Among IP addresses, public IPv4 addresses are of great significance for commercial needs. With your own public IPv4 address, you can set up a server on demand, submit an application and register it, and use the public IP to build a website, thus reaching users around the world.

Therefore, the exhaustion of IPv4 addresses is an enduring industry topic. IPv4 addresses are becoming an increasingly scarce resource, and for more than four years, organizations that want to acquire new public IPv4 addresses have had to reclaim them from organizations that have shut down or have migrated to IPv6. With supply exceeding demand, the cost of obtaining IPv4 addresses has also risen.

AWS also mentioned this when explaining why it charges. AWS chief evangelist Jeff Barr wrote on the company's news blog:

Over the past five years, the cost of purchasing a single public IPv4 address has increased by more than 300%. This change reflects our own costs and is also designed to encourage you to be more frugal when using public IPv4 addresses and consider accelerated adoption of IPv6 as a modernization and protection measure.

Under the new pricing strategy, starting February 1, 2024, all public IPv4 addresses will be charged $0.005 per IP per hour, regardless of whether they are attached to the service or not.

It is worth noting that the official statement states that this change applies to all AWS services in all AWS regions (Business, AWS China, and GovCloud), which means that domestic Amazon Cloud Technology users will also be affected.   

2. Chain reactions under the new price strategy

The fee of half a cent per IP per hour may not seem like much, but if the customer uses a large number of addresses, the fee can gradually add up to a staggering degree over time.

Moreover, the AWS services involved in this move include Amazon Elastic Compute Cloud (Amazon EC2), Amazon Relational Database Service (RDS) database instances, Amazon Elastic Kubernetes Service (EKS) nodes, and other AWS services that can allocate and attach public IPv4 addresses.

Screenshot: Amazon AWS official blog

However, customers will not be charged for their own IP addresses using the AWS Bring Your Own IP (BYOIP) feature. At the same time, AWS offers an EC2 free tier, which includes 750 hours of public IPv4 address usage per month within 12 months from the effective date of the charging policy.

As an AWS customer, Paul Copplestone maintains a very rational attitude towards this charging policy.

He admitted: "The charge is $0.005 per hour, which is equivalent to about $4 per address per month. I can't imagine how many companies are willing to pay for this to continue using IPv4 addresses. Although for a single user, $4 is relatively small , but I'm guessing that for an infrastructure company like Supabase, the impact of this fee cannot be ignored - we provide a full EC2 instance for every Postgres database, which means this change will affect our AWS bill Add millions of dollars."

In Copplestone's view, the impact of this change will be felt gradually. Once the charges are implemented, infrastructure services companies will notice an increase in their bills. Under this pressure, we must face several choices: first, pass the cost to customers; second, provide a solution (for example, using a proxy); third, start removing IPv4, formally seek the road to IPv6, and I hope the world can also keep pace with the times.

3. IPv4 has been exhausted for so long, why didn’t we notice it?

IPv6 is a next-generation IP protocol designed for exhaustion of IPv4 address resources. Compared with the 32-bit address format of IPv4, IPv6 uses a 128-bit address format, which can provide an order of magnitude larger unique IP address.

The address inventory of IPv4 can only meet the needs of about 4.3 billion devices, while IPv6 is expected to generate about 340 trillion (340 times 10 to the 27th power) addresses, which is theoretically close to infinite.

Since the advantages of IPv6 are so great, why is there such slow progress in replacing IPv4? More directly, IPv4 addresses have been exhausted for so long, so why do we have no sense of change?

The key is that in order to cope with the exhaustion of IPv4 addresses, in addition to upgrading IPv6, organizations and Internet service providers (ISPs) have also found many practical transition solutions. for example:

1. IPv4 leasing: Allows IPv4 address holders to lease unused address space to users in need at an agreed price.

2. Network Address Translation (NAT): During the data packet transmission process, multiple device IPs from the private network are mapped to a public IPv4 address, so that multiple devices can share the same public IP address to access the Internet.

3. Classless inter-domain routing (CIDR): Eliminates the boundaries of IP address categories, allowing the IPv4 address space to be divided into subnets to adapt to different address allocation schemes. Through CIDR, limited IPv4 address resources can be utilized more efficiently.

Combined, these technologies greatly ease the pressure to quickly switch to IPv6 because they can exponentially increase the number of connected devices on a single IP address. But this also makes load balancing and traffic redirection more complex and difficult. As the number of Internet devices grows, although these technologies have temporarily delayed the urgency of transition to IPv6, in the long run, the comprehensive deployment of IPv6 is still the fundamental way to solve the problem of address exhaustion.

4. Several major factors affecting the popularity of IPv6

Although everyone knows that IPv6 is a beneficial technology. But back to the present, the popularization of IPv6 still faces many challenges. Tucker Preston, senior system engineer at Gcore, boils it down to three points:

First, compatibility and complexity. Most existing systems (computers, networks, routers) are designed to work with IPv4, and IPv6 lacks backward compatibility with these legacy systems and network equipment. This means organizations may need a comprehensive network infrastructure upgrade to support IPv6, which can be a complex task.

And the transition to IPv6 may also affect customers whose equipment is not IPv6-compatible. Most companies are hesitant to adopt IPv6 in order to avoid potential revenue losses caused by customers migrating to IPv4-compatible competitors.

Second, transition costs. Due to compatibility gaps, transitioning to IPv6 requires system upgrades. This may mean purchasing and deploying new (often expensive) network infrastructure such as routers and switches.

Not to mention, most organizations' IT departments are only familiar with IPv4 infrastructure and addresses. Adopting IPv6 will require investments in IT staff training and software migration, which can result in significant soft costs, especially for entities with complex network configurations.

Third, Internet service providers (ISPs) are poorly prepared. ISPs play a key role in the transition to IPv6. However, due to the slow adoption of IPv6 by ISPs, the challenges of compatibility issues and cost inefficiency are more prominent. Since ISPs control large areas of the network and its associated infrastructure, organizations may decide that it is not cost-effective to make the transition when many ISPs do not yet have the facilities to effectively implement IPv6.

In addition, if there is no ISP to provide strong IPv6 support, users may encounter connection problems or be unable to access IPv6-enabled websites, which further hinders the popularity and application of IPv6. Only when ISPs comprehensively upgrade their network infrastructure to adapt to IPv6 and provide stable and reliable IPv6 services can they effectively promote the smooth transition of the entire industry.

Coppleston also believes that ISP's lack of support for IPv6 is a major reason that hinders the popularity of IPv6. In addition, based on Supabase's production practice, he also mentioned that many developer tools are not yet fully configured for IPv6. Their data team needed to make the following changes in order to support IPv6 in their toolchain:

• Add IPv6 support for VPC networks.
• Added IPv6 support for Airflow virtual machines (VMs).
• Add IPv6 support for Docker and Compose.

Coppleston concludes: What seems like a small change actually involves a lot of work. Because this not only involves an in-depth understanding of the basic configuration, but also requires careful adjustment and testing at multiple levels.

5. Be prepared to respond

Although IPv6 is unlikely to be popularized immediately, and IPv6 and IPv4 may even experience a long period of coexistence, IPv6 replacing IPv4 is the inevitable trend. The sooner relevant technical adjustments and upgrades are made, the sooner we may be able to take the initiative.

Including but not limited to: contacting ISPs to confirm whether they have fully supported IPv6 and requesting necessary technical support and service upgrades; for enterprises using cloud services, they need to understand and test their IPv6-related functions and services to facilitate subsequent smooth migration; Ensure that your network devices (such as routers, switches, etc.) support IPv6 and configure them accordingly; provide the developer team with necessary training and support to familiarize them with IPv6-related development and deployment processes.

In short, take AWS's charging policy as a signal to avoid being impatient and prepare for the arrival of IPv6.

References:

https://tech.slashdot.org/story/23/08/01/0013249/aws-to-start-charging-for-public-ipv4-addresses

https://aws.amazon.com/cn/blogs/china/new-aws-public-ipv4-address-charge-public-ip-insights/    

https://www.zhihu.com/question/615010105

https://supabase.com/blog/ipv6

https://thenewstack.io/why-is-ipv6-adoption-slow/